Analysis on the influence of ZnO addition on microwave dielectric properties of Li_2MgSiO_4 ceramics

摘要

Dielectric ceramics have gained wide attention owing to their applicability in a broad range of domains including a microwave communication system. Silicates are considered as the prospective substrate materials for microwave circuits due to their properties complementing with the requisites of a microwave substrate. Lightweight lithium-based silicate ceramic namely lithium magnesium silicate (Li2MgSiO4, LMS) was prepared by a solid-state reaction method. Zinc oxide (ZnO) was used as an additive to LMS in different weight percentages (0.5, 1.0, 1.5 and 2.0) and LMS-ZnO ceramics were also prepared. The microwave dielectric properties of pure LMS and ZnO-added LMS were measured and the influence of ZnO on LMS was investigated. A dielectric resonance technique was utilized to study the dielectric properties of ceramic samples at 12 GHz. A comparatively higher quality factor of 24,000 GHz was attained by the LMS-ZnO (2wt%) system with a relative density of 90.2% and < 10 dielectric constant of 5.76 making it suitable for substrate applications.